Note 2 - Investment Securities (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	$ 12,170,000	$ 13,625,000
Available-for-sale securities, gross unrealized losses	21,000
Available-for-sale securities, gross unrealized gains	(52,000)	(212,000)
Available-for-sale securities	12,139,000	13,413,000
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	9,000,000	9,000,000
Available-for-sale securities, gross unrealized losses		71,000
Available-for-sale securities, gross unrealized gains	(102,000)	(61,000)
Available-for-sale securities	8,898,000	9,010,000
Subordinated Notes [Member]
Available-for-sale securities, amortized cost	2,000,000	2,000,000
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, gross unrealized gains
Available-for-sale securities	2,000,000	2,000,000
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost		5,000,000
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, gross unrealized gains		(46,000)
Available-for-sale securities		4,954,000
Available-for-sale securities, amortized cost	23,170,000	29,625,000
Available-for-sale securities, gross unrealized losses	21,000	71,000
Available-for-sale securities, gross unrealized gains	(154,000)	(319,000)
Available-for-sale securities	$ 23,037,000	$ 29,377,000

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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